类型定义不正确

[feeops]

type DataInDescribeInstanceBill struct {
	BillingCycle string                        `json:"BillingCycle" xml:"BillingCycle"`
	AccountID    string                        `json:"AccountID" xml:"AccountID"`
	AccountName  string                        `json:"AccountName" xml:"AccountName"`
	TotalCount   int                           `json:"TotalCount" xml:"TotalCount"`
	NextToken    string                        `json:"NextToken" xml:"NextToken"`
	MaxResults   int                           `json:"MaxResults" xml:"MaxResults"`
	Items        []ItemsInDescribeInstanceBill `json:"Items" xml:"Items"`
}

// ItemsInDescribeInstanceBill is a nested struct in bssopenapi response
type ItemsInDescribeInstanceBill struct {
	Item []Item `json:"Item" xml:"Item"`
}

Items又嵌入Item，双层数组，不太对吧？